SPI Driver for Enhanced Relay Control

SPIDER - TLE7243SL

Protection Functions

Datasheet

16

Rev. 1.0, 2009-09-30

6

Protection Functions

The device provides embedded protective functions. Integrated protection functions are designed to prevent IC

destruction under fault conditions described in this datasheet. Fault conditions are considered as “outside” normal

operating range. Protection functions are not designed for continuous repetitive operation.

6.1

Over Load Protection

loaded channel n switches off and the according diagnosis flag Dn is set.The channel can be switched on after

clearing the diagnosis flag. Please refer to Figure 7 for details.

Figure 7

Shut down at over load

The current sink to ground ensures that the channels switch off in case of open input pin. The zener diode protects

the input circuit against ESD pulses. After power-on reset, the device enters idle mode.

6.2

Over Temperature Protection

A temperature sensor for each channel causes an overheated channel n to switch off to prevent destruction and

the according diagnosis flag Dn is set. The channel can be switched on after clearing the diagnosis flag. Please

refer to Chapter 7.1 for information on diagnosis features.

6.3

Reverse Polarity Protection

In case of reverse polarity, the intrinsic body diode of the power transistor causes power dissipation. The reverse

current through the intrinsic body diode of the power transistor has to be limited by the connected load. The

V

DD

and

V

protection is not active during reverse polarity.

IN1

t

t

OverLoad.emf

I

OUT(OVL)

Program OUT 1 to

STANDBY and to

IN1 again